This directory contains data used by Korg.  Because it's tracked in git, we try to keep this data
from being larger than necessary.

These are all the places data used by Korg can be stored, in order from smallest to largest.
- Directly in the source code.  When a table of data is small, it is often included directly as an
  Array in the source code.  See for example the Korg.ContinuumAbsoprtion.Peach1970 module.
- In this directory. Files here are sometimes in their original format, and sometimes repackaged in 
  HDF5 format for size or ease of access.  If the original data files are small, they will be
  included here.  If they are large (> a few MB), they will be in the...
- Korg_data repository (https://github.com/ajwheeler/Korg_data).  This is where we archive large-ish
  files not used directly by Korg, but from which we created repacked HDF5 files.
- Files too large for github (> 100 MB) can be fetched by Korg and placed in the $KORG_DATA_DIR 
  directory (default: ~/.korg). So far this is only used for the grid of model atmospheres
  interpolated by Korg.interpolate_marcs. 
